A caul plate is a plate or sheet that is used to transfer pressure and/or heat to a composite lay-up. In addition, the caul plate may protect an uncured part from undesirable defects. The caul plate is typically placed proximate a lay-up prior to a curing process of a composite part. Mandrels, or other load generating devices, are used to load the caul plate and/or secure a stiffening structure. The mandrels cause the caul plate to exert a substantially perpendicular force against the lay-up during the curing process. When used properly and under normal circumstances, caul plates enable the creation of a smooth surface on a finished part.
Traditionally, caul plates are reused in a composite part curing process until the caul plate is no longer capable of creating a defect-free surface on a finished part. A defect in the caul plate often results in a rejected finished part because defects in the caul plate are transferred to the part. During the setup of the curing process, the caul plates are often positioned over a protective sheet (e.g., Teflon® sheet) and then secured to the lay-up using adhesive tape, requiring the use of additional materials. After each curing process, the caul plate must be removed from the lay-up and cleaned, or otherwise prepared for reuse. The caul plate maintenance may be time consuming in some instances.
Therefore, techniques and apparatus to improve caul plates for manufacture of composite lay-ups have utility.